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Pickett, CW, Nosaka, K, Zois, J, Hopkins, WG, and Blazevich, AJ. Maximal upper-body strength and oxygen uptake are associated with performance in high-level 200-m sprint kayakers. J Strength Cond Res 32(11): 3186-3192, 2018-Current training and monitoring methods in sprint kayaking are based on the premise that upper-body muscular strength and aerobic power are both important for performance, but limited evidence exists to support this premise in high-level athletes. Relationships between measures of strength, maximal oxygen uptake (V[Combining Dot Above]O2max), and 200-m race times in kayakers competing at national-to-international levels were examined. Data collected from Australian Canoeing training camps and competitions for 7 elite, 7 national, and 8 club-level male sprint kayakers were analyzed for relationships between maximal isoinertial strength (3 repetition maximum bench press, bench row, chin-up, and deadlift), V[Combining Dot Above]O2max on a kayak ergometer, and 200-m race time. Correlations between race time and bench press, bench row, chin-up, and V[Combining Dot Above]O2max were -0.80, -0.76, -0.73, -0.02, and 0.71, respectively (90% confidence limits ∼±0.17). The multiple correlation coefficient for 200-m race time with bench press and V[Combining Dot Above]O2max was 0.84. Errors in prediction of 200-m race time in regression analyses were extremely large (∼4%) in relation to the smallest important change of 0.3%. However, from the slopes of the regressions, the smallest important change could be achieved with a 1.4% (±0.5%) change in bench-press strength and a 0.9% (±0.5%) change in V[Combining Dot Above]O2max. Substantial relationships were found between upper-body strength or aerobic power and 200-m performances. These measures may not accurately predict individual performance times, but would be practicable for talent identification purposes. Training aimed at improving upper-body strength or aerobic power in lower performing athletes could also enhance the performance in 200-m kayak sprints.

The specificity of contemporary training practices of international rugby sevens players is unknown. We quantified the positional group-specific activity profiles and physiological demands of on-field training activities and compared these with match demands. Twenty-two international matches and 63 rugby-specific training drills were monitored in 25 backs and 17 forwards from a national squad of male rugby sevens players over a 21-month period. Drills were classified into 3 categories: low-intensity skill refining (n = 23 drills, 560 observations), moderate- to high-intensity skill refining (n = 28 drills, 600 observations), and game simulation (n = 12 drills, 365 observations). Movement patterns (via Global Positioning System devices) and physiological load (via heart rate monitors) were recorded for all activities, and the differences between training and matches were quantified using magnitude-based inferential statistics. Distance covered in total and at ≥3.5 m·s, maximal velocity, and frequency of accelerations and decelerations were lower for forwards during competition compared with those for backs by a small but practically important magnitude. No clear positional group differences were observed for physiological load during matches. Training demands exceeded match demands only for frequency of decelerations of forwards during moderate- to high-intensity skill-refining drills and only by a small amount. Accelerations and distance covered at ≥6 m·s were closer to match values for forwards than for backs during all training activities, but training drills consistently fell below the demands of international competition. Coaches could therefore improve physical and physiological specificity by increasing the movement demands and intensity of training drills.

Lipinska, P, and Hopkins, WG. Pacing profiles and competitive performance of elite female 400-m freestyle swimmers. J Strength Cond Res 34(1): 218-224, 2020-Pacing can impact competitive endurance performance. The objective of this study was to determine relationships between pacing parameters and competitive performance of elite female 400-m freestyle swimmers. Publicly available websites provided 50-m split and final times for 381 swims of 20 elite female swimmers in over 150 national and international competitions between 2004 and 2016. Most pacing profiles displayed negative quadratic curvature, with the fifth of the 8 laps being the median slowest. The mean times for the first and last laps were faster than predicted by the quadratic by 5.6 and 1.9%, respectively, and lap-to-lap variability was 0.65%. Scatter plots of each swimmer's final time often showed no obvious relationships with their pacing parameters, suggesting that swimmers compensated for changes in one parameter with changes in another. However, some plots showed a U shape or linear trend that allowed tentative identification of optimum values of the pacing parameters. In these plots, it was apparent that about half the swimmers might make small to moderate improvements (up to ∼1%) by changing the slope or curvature of their pacing profile or by changing time in the first or last laps. This approach for characterizing pacing profiles to identify possible improvements might be appropriate to assess pacing in other sports with multiple laps, frequent competitions, and relatively constant environmental conditions.

Numerous studies have highlighted differences between playing levels and positions in rugby union; however, few studies have investigated longitudinal progressions of body composition and physical performance. Between-player differences and within-player changes in body composition, strength, power, speed, and repeated sprint ability, from 1,161 New Zealand rugby union players from 2004 to 2007, were estimated using a mixed modeling procedure. Props had the highest mass, percent body fat, strength, and slowest speed times compared with the other positions, whereas outside backs had the fastest speed time and lowest percent body fat. For most measures, there were small-to-moderate differences (range, 1.1-14%) between players selected and not selected for provincial teams and small-to-large differences (range, 1.8-15%) between provincial and Super Rugby (professional) players. The faster 20-m sprint times in international compared with Super Rugby players was small in magnitude for both the forwards (1.9%) and backs (2.2%). The average annual improvements were small to moderate for strength (range, 2.1-15%) and small for repeated sprint ability within the lower playing levels (~1.5%). Small increases occurred in lower body strength (~7.0%) as players moved from Super Rugby to provincial competition. Small decreases in sprint time (~1.6%) and small increases in strength (~6.3%) occurred as players moved from Super Rugby to midyear international competition. The differences between levels in performance provide level-specific characteristics from Super Rugby and below, but international players may be selected because of greater skill and experience. Changes in physical performance between competitions may be a result of reduced training loads because of regular high-intensity matches and greater travel involved in the Super Rugby competition.

The specificity of contemporary training practices of international rugby sevens players is unknown. We quantified the positional group-specific activity profiles and physiological demands of on-field training activities and compared these with match demands. Twenty-two international matches and 63 rugby-specific training drills were monitored in 25 backs and 17 forwards from a national squad of male rugby sevens players over a 21-month period. Drills were classified into 3 categories: low-intensity skill refining (n = 23 drills, 560 observations), moderate- to high-intensity skill refining (n = 28 drills, 600 observations), and game simulation (n = 12 drills, 365 observations). Movement patterns (via Global Positioning System devices) and physiological load (via heart rate monitors) were recorded for all activities, and the differences between training and matches were quantified using magnitude-based inferential statistics. Distance covered in total and at ≥3.5 m·s, maximal velocity, and frequency of accelerations and decelerations were lower for forwards during competition compared with those for backs by a small but practically important magnitude. No clear positional group differences were observed for physiological load during matches. Training demands exceeded match demands only for frequency of decelerations of forwards during moderate- to high-intensity skill-refining drills and only by a small amount. Accelerations and distance covered at ≥6 m·s were closer to match values for forwards than for backs during all training activities, but training drills consistently fell below the demands of international competition. Coaches could therefore improve physical and physiological specificity by increasing the movement demands and intensity of training drills.

Elastic band assisted and resisted jump training may be a novel way to develop lower-body power. The purpose of this investigation was to (a) determine the kinetic differences between assisted, free, and resisted countermovement jumps and (b), investigate the effects of contrast training using either assisted, free, or resisted countermovement jump training on vertical jump performance in well-trained athletes. In part 1, 8 recreationally trained men were assessed for force output, relative peak power (PP·kg(-1)) and peak velocity during the 3 types of jump. The highest peak force was achieved in the resisted jump method, while PP·kg(-1) and peak velocity were greatest in the assisted jump. Each type of jump produced a different pattern of maximal values of the variables measured, which may have implications for developing separate components of muscular power. In part 2, 28 professional rugby players were assessed for vertical jump height before and after 4 weeks of either assisted (n = 9), resisted (n = 11), or free (n = 8) countermovement jump training. Relative to changes in the control group (1.3 ± 9.2%, mean ± SD), there were clear small improvements in jump height in the assisted (6.7 ± 9.6%) and the resisted jump training group (4.0 ± 8.8%). Elastic band assisted and resisted jump training are both effective methods for improving jump height and can be easily implemented into current training programs via contrast training methods or as a part of plyometric training sessions. Assisted and resisted jump training is recommended for athletes in whom explosive lower-body movements such as jumping and sprinting are performed as part of competition.

Resistance training at the load that maximizes peak power (Pmax) may produce greater increases in peak power than other loads. Pmax for lower-body lifts can occur with no loading but whether Pmax can be increased further with negative loading is unclear. The purpose of this investigation was therefore to determine lower-body Pmax (jump squat) using a spectrum of loads. Box squat 1 repetition maximum (1RM) was measured in 18 elite rugby-union players. Pmax was then determined using loads of -28 to 60%1RM. Elastic bands were used to unload body weight for negative loads. Jump squat Pmax occurred with no loading (body weight: 8,880 ± 2,186 W) in all but 2 subjects. There was a discontinuity in the power-load relationship for the jump squat, possibly because of the increased countermovement in the body weight jump. The self-selected depth (dip) before the propulsive phase of the jump was greater by 24 ± 11 to 40 ± 16% (moderate to large effect size) than all positive loads. These findings highlight methodological issues that need to be taken into consideration when comparing power outputs of loaded and unloaded jumps.

The purpose of this investigation was to assess changes in strength, power, and levels of testosterone and cortisol over a 13-week elite competitive rugby union season. Thirty-two professional rugby union athletes from a Super 14 rugby team (age, 24.4 +/- 2.7 years; height, 184.7 +/- 6.2 cm; mass, 104.0 +/- 11.2 kg; mean +/- SD) were assessed for upper-body and lower-body strength (bench press and box squat, respectively) and power (bench throw and jump squat, respectively) up to 5 times throughout the competitive season. Salivary testosterone and cortisol samples, along with ratings of perceived soreness and tiredness, were also obtained before each power assessment. An effect size of 0.2 was interpreted as the smallest worthwhile change. A small increase in lower-body strength was observed over the study period (8.5%; 90% confidence limits +/-7.2%), whereas upper-body strength was maintained (-1.2%; +/-2.7%). Decreases in lower-body power (-3.3%; +/-5.5%) and upper-body power (-3.4; +/-4.9%) were small and trivial. There were moderate increases in testosterone (54%; +/-27%) and cortisol (97%; +/-51%) over the competitive season, and the testosterone to cortisol ratio showed a small decline (22%; +/-25%), whereas changes in perceived soreness and tiredness were trivial. Individual differences over the competitive season for all measures were mostly trivial or inestimable. Some small to moderate relationships were observed between strength and power; however, relationships between hormonal concentrations and performance were mainly trivial but unclear. Positive adaptation in strength and power may be primarily affected by cumulative training volume and stimulus over a competitive season. Greater than 2 resistance sessions per week may be needed to improve strength and power in elite rugby union athletes during a competitive season.

Strength testing is often used with team-sport athletes, but some measures of strength may have limited prognostic/diagnostic value in terms of the physical demands of the sport. The purpose of this study was to investigate relationships between sprint ability and the kinetic and kinematic outputs of a machine squat jump. Thirty elite level rugby union and league athletes with an extensive resistance-training background performed bilateral concentric-only machine squat jumps across loads of 20% to 90% 1 repetition maximum (1RM), and sprints over 10 meters and 30 or 40 meters. The magnitudes of the relationships were interpreted using Pearson correlation coefficients, which had uncertainty (90% confidence limits) of approximately +/-0.3. Correlations of 10-meter sprint time with kinetic and kinematic variables (force, velocity, power, and impulse) were generally positive and of moderate to strong magnitude (r = 0.32-0.53). The only negative correlations observed were for work, although the magnitude was small (r = -0.18 to -0.26). The correlations for 30- or 40-meter sprint times were similar to those for 10-meter times, although the correlation with work was positive and moderate (r = 0.35-0.40). Correlations of 10-meter time with kinetic variables expressed relative to body mass were generally positive and of trivial to small magnitude (r = 0.01-0.29), with the exceptions of work (r = -0.31 to -0.34), and impulse (r = -0.34 to -0.39). Similar correlations were observed for 30- and 40-meter times with kinetic measures expressed relative to body mass. Although correlations do not imply cause and effect, the preoccupation with maximizing power output in this particular resistance exercise to improve sprint ability appears problematic. Work and impulse are potentially important strength qualities to develop in the pursuit of improved sprinting performance.

The load that maximizes mechanical power output (Pmax) has received considerable research attention owing to its perceived importance to training prescription. However, it may be that identifying Pmax is of little importance if the difference in power output about Pmax is insubstantial. Additionally, comparing the effect of load on power output between studies is problematic due to various methodological differences. The purpose of this study therefore was to quantify the concentric power output for a machine squat-jump across a spectrum of loads (10-100% of 1 repetition maximum [1RM]). To estimate Pmax load and proximate loads a quadratic was fitted to the power output (Watts) and load (% of 1RM) of 18 well-trained rugby athletes. Pmax for peak and mean power output occurred at 21.6 +/- 7.1% of 1RM (mean +/- SD) and 39.0 +/- 8.6% of 1RM, respectively. A 20% change in load either side of the maximum resulted in a mean decrease of only 9.9% (90% confidence limits +/-2.4%) and 5.4% (+/-0.9%) in peak and mean power respectively; standard deviations about these means (representing individual differences in the decrease) were 6.0% and 2.1%, respectively (90% confidence limits x//1.34). It appears that most athletes have a broad peak in their power profile for peak or mean power. The preoccupation of identifying one load for maximizing power output would seem less meaningful than many practitioners and scientists believe.

Athletes in sports requiring explosive movements might benefit from a unique form of training in which a limb is restrained while the athlete attempts ballistic (explosive) movements. We investigated the effects of such ballistic training and conventional resistance training on force and speed of front kicks, side kicks, and palm strikes of martial artists. We assigned subjects randomly to an experimental group (n = 13) or a control (normal martial art training) group (n = 9). Conventional resistance training produced a gain of 12% (95% likely limits +/- 13%) in front kick force relative to the control group. Overall ballistic training and conventional resistance training decreased side kick force by 15% (+/-14%), but movement speeds increased by 11-21% (+/-13-17%). Responses to ballistic training were generally more marked in more highly skilled athletes. Attempted ballistic training may be a beneficial adjunct to resistance training for skilled athletes in sports where speed rather than force is critical.

Substantial variation in the load that produces maximal power has been reported. It has been suggested that the variation observed may be due to differences in subjects' physical characteristics. Therefore, the aim of this study was to determine the extent in which anthropometric measures correlate with the load that produces maximal power. Anthropometric measures (upper-arm length, forearm length, total arm length, and upper-arm girth) and bench press strength were assessed in 26 professional rugby union players. Peak power was then determined in the bench press throw exercise using loads of 20-60% of one repetition maximum (1RM) in the bench press exercise. Maximal power occurred at 30 ± 14% 1RM (mean ± SD). Upper-arm length had the highest correlation with the load maximizing power: -0.61 (90% confidence limits -0.35 to -0.78), implying loads of 22 vs. 38% 1RM maximize power for players with typically long vs. short upper-arm length. Correlations for forearm length, total arm length, and upper-arm girth to the load that maximized power were -0.29 (0.04 to -0.57), -0.56 (-0.28 to -0.75), and -0.29 (0.04 to -0.57), respectively. The relationship between 1RM and the load that produced maximal power was r = -0.23 (0.10 to -0.52). The between-subject variation in the load that maximized power observed (SD = ±14% of 1RM) may have been due to differences in anthropometric characteristics, and absolute strength and power outputs. Indeed, athletes with longer limbs and larger girths and greater maximal strength and power outputs used a lower percentage of 1RM loads to achieve maximum power. Therefore, we recommend individual assessment of the load that maximizes power output.

Argus, CK, Gill, ND, Keogh, JWL, and Hopkins, WG. Acute effects of verbal feedback on upper-body performance in elite athletes. J Strength Cond Res 25(12): 3282-3287, 2011-Improved training quality has the potential to enhance training adaptations. Previous research suggests that receiving feedback improves single-effort maximal strength and power tasks, but whether quality of a training session with repeated efforts can be improved remains unclear. The purpose of this investigation was to determine the effects of verbal feedback on upper-body performance in a resistance training session consisting of multiple sets and repetitions in well-trained athletes. Nine elite rugby union athletes were assessed using the bench throw exercise on 4 separate occasions each separated by 7 days. Each athlete completed 2 sessions consisting of 3 sets of 4 repetitions of the bench throw with feedback provided after each repetition and 2 identical sessions where no feedback was provided after each repetition. When feedback was received, there was a small increase of 1.8% (90% confidence limits, ±2.7%) and 1.3% (±0.7%) in mean peak power and velocity when averaged over the 3 sets. When individual sets were compared, there was a tendency toward the improvements in mean peak power being greater in the second and third sets. These results indicate that providing verbal feedback produced acute improvements in upper-body power output of well-trained athletes. The benefits of feedback may be greatest in the latter sets of training and could improve training quality and result in greater long-term adaptation.

The combination of resistance and plyometric training, or complex training, may yield greater functional gains than either method alone. As steroid hormones respond to exercise stimuli and modulate the functional outcomes, it is possible that complex training creates an enhanced anabolic physiological milieu for adaptation. We investigated acute responses of salivary testosterone and cortisol to complex exercise bouts. After a standardized warm-up, 16 semiprofessional rugby players performed 1 of 4 exercise bouts in a cross-over manner: power-power; power-strength; strength-power; or strength-strength. Each player completed each of the 4 bouts twice over a 4-week period in a balanced random order such that each player performed a total of 8 bouts. The power block consisted of 3 sets of 3 repetitions of jump squat exercise at 50% of 1-repetition maximum load. The strength block consisted of three sets of three repetitions of box squat exercise at a 3-repetition maximum load. There were 3-minute rest periods between sets and 4-minute rest periods between exercise blocks. Saliva was sampled before, during, and immediately after the exercise bout. The greatest overall hormonal responses were a small increase in testosterone (13%; 90% confidence limits ± 7%) and a trivial increase in cortisol (27%; ± 30%) after the strength-power bout. A clear difference was observed between the strength-power and the power-power bouts immediately after exercise for testosterone (10%; ± 8%) and cortisol (29%; ± 17%). The preceding exercise block had little effect on subsequent strength and power performance. The hormonal response after the strength-power bout suggests that this exercise sequence provides an enhanced anabolic milieu for adaptation.

The ability to monitor training is critical to the process of quantifying training periodization plans, yet weekly patterns of volume and intensity for Paralympic swimmers before competition have not been reported. Sixteen swimmers were monitored prospectively over a 16-week training block constituting 4 training phases (early, mid, late, and taper), before a World Championship. Training volume (total and main set distance) and intensity (percentage of peak heart rate [HR], swimming velocity, and rate of perceived exertion [RPE]) were quantified using an online training diary, and changes in training load were examined over the 4 training phases. For a subgroup of swimmers (n = 12), with similarities in underlying disability, change in performance between Selection Trials and World Championships was also quantified. Substantial increases in total training volume (29.6%) were observed late phase, and main set volume was reduced substantially (24.1%) during the taper phase. Small to moderate increases in training intensity (HR 2.4%, velocity 4.5%, and RPE 6.7%) were observed late phase and maintained through the taper. There were no clear associations between discrete training measures and competition performance. Swimmers competing at the Paralympic level seem to follow traditional periodized patterns of training, similar to those of swimmers at the Olympic level, before competition. Coaches of elite swimmers with a disability should review their prescribed patterns of training before major competition: A more substantial taper (larger reduction in volume) could elicit a greater improvement in performance. Training prescription should account for different disabilities and classes and individual circumstances of elite swimmers with a disability.

The effect of repeated exposures to natural and simulated moderate altitude on physiology and competitive performance of elite athletes warrants further investigation. This study quantified changes in hemoglobin mass, performance tests, and competitive performance of elite swimmers undertaking a coach-prescribed program of natural and simulated altitude training. Nine swimmers (age 21.1 +/- 1.4 years, mean +/- SD) completed up to four 2-week blocks of combined living and training at moderate natural altitude (1,350 m) and simulated live high-train low (2,600-600 m) altitude exposure between 2 National Championships. Changes in hemoglobin mass (Hbmass), 4-mM lactate threshold velocity, and 2,000 m time trial were measured. Competition performance of these swimmers was compared with that of 9 similarly trained swimmers (21.1 +/- 4.1 years) who undertook no altitude training. Each 2-week altitude block on average produced the following improvements: Hbmass, 0.9% (90% confidence limits, +/-0.8%); 4-mM lactate threshold velocity, 0.9% (+/-0.8%); and 2,000 m time trial performance, 1.2% (+/-1.6%). The increases in Hbmass had a moderate correlation with time trial performance (r = 0.47; +/-0.41) but an unclear correlation with lactate threshold velocity (r = -0.23; +/-0.48). The altitude group did not swim faster at National Championships compared with swimmers who did not receive any altitude exposure, the difference between the groups was not substantial (-0.5%; +/-1.0%). A coach-prescribed program of repeated altitude training and exposure elicited modest changes in physiology but did not substantially improve competition performance of elite swimmers. Sports should investigate the efficacy of their altitude training program to justify the investment.

Training at a load maximizing power output (Pmax) is an intuitively appealing strategy for enhancement of performance that has received little research attention. In this study we identified each subject's Pmax for an isoinertial resistance training exercise used for testing and training, and then we related the changes in strength to changes in sprint performance. The subjects were 18 well-trained rugby league players randomized to two equal-volume training groups for a 7-week period of squat jump training with heavy loads (80% 1RM) or with individually determined Pmax loads (20.0-43.5% 1RM). Performance measures were 1RM strength, maximal power at 55% of pretraining 1RM, and sprint times for 10 and 30 m. Percent changes were standardized to make magnitude-based inferences. Relationships between changes in these variables were expressed as correlations. Sprint times for 10 m showed improvements in the 80% 1RM group (-2.9 +/- 3.2%) and Pmax group (-1.3 +/- 2.2%), and there were similar improvements in 30-m sprint time (-1.9 +/- 2.8 and -1.2 +/- 2.0%, respectively). Differences in the improvements in sprint time between groups were unclear, but improvement in 1RM strength in the 80% 1RM group (15 +/- 9%) was possibly substantially greater than in the Pmax group (11 +/- 8%). Small-moderate negative correlations between change in 1RM and change in sprint time (r approximately -0.30) in the combined groups provided the only evidence of adaptive associations between strength and power outputs, and sprint performance. In conclusion, it seems that training at the load that maximizes individual peak power output for this exercise with a sample of professional team sport athletes was no more effective for improving sprint ability than training at heavy loads, and the changes in power output were not usefully related to changes in sprint ability.

Athletes in sports requiring explosive movements might benefit from a unique form of training in which a limb is restrained while the athlete attempts ballistic (explosive) movements. We investigated the effects of such ballistic training and conventional resistance training on force and speed of front kicks, side kicks, and palm strikes of martial artists. We assigned subjects randomly to an experimental group (n = 13) or a control (normal martial art training) group (n = 9). Conventional resistance training produced a gain of 12% (95% likely limits +/- 13%) in front kick force relative to the control group. Overall ballistic training and conventional resistance training decreased side kick force by 15% (+/-14%), but movement speeds increased by 11-21% (+/-13-17%). Responses to ballistic training were generally more marked in more highly skilled athletes. Attempted ballistic training may be a beneficial adjunct to resistance training for skilled athletes in sports where speed rather than force is critical.